Histopathological evaluation of brain and retina of adult zebrafish exposed to silver nitrate

The purpose of the study was to assess the histological alterations in the adult zebrafish (Danio rerio L.) brain and retina after long-term exposure to silver nitrate (AgNO3) at concentrations of 6.25, 12.5, 25, and 50 & mu;g/L for 28 days. Although zebrafish subjected to varying concentrations ofAgNO3 did not die, they did demonstrate a progression in the anatomical abnormalities in their brains. Following exposure to silver nitrate at various concentrations for 28 days, mild to moderate pathological changes have been seen in the corpus cerebella, hypothalamus, lobuscaudalis cerebella, medulla, and dorsal telencephalic area of the opticum tectum in the brain, but there have been no discernible changes in the retina. It was concluded that silver nitrate has the potential to harm the nervous system.